diff --git a/db/migrate/2_add_missing_unique_indices.rb b/db/migrate/2_add_missing_unique_indices.rb
index 769f9235c..80c33d027 100644
--- a/db/migrate/2_add_missing_unique_indices.rb
+++ b/db/migrate/2_add_missing_unique_indices.rb
@@ -13,7 +13,7 @@ def self.down
     remove_index :tags, :name
 
     remove_index :taggings, name: 'taggings_idx'
-    add_index :taggings, :tag_id
+
     add_index :taggings, [:taggable_id, :taggable_type, :context]
   end
 end